MR. J. C. GALTON ON DASYPUS SEXC1NCTUS. o.J 



The coraco-brachialis in Cholcepus didactylus is a thin, cord-like muscle of uniform 

 size, and, like its homologue in Bradypus, as described by Mr. Wood in the paper t<> 

 which I have already made reference, represents the ordinary or middle variety only of 

 the muscle. 



Among other animals in which, through the kindness of Prof. Holiest on, I have been 

 enabled to examine and make sketches of this muscle arc Moor op us tamandua^ M. ritji- 

 collis (var. Bennetti 1 ), Phascolomys wombata, and a specimen of Hysirir (crista fa, 1 

 think) . 



In the Tamandua this muscle arises from that portion of the superior edge of the 

 scapula which is anterior to the omohyoidean notch (or foramen), and which may 

 represent a rudimentary coracoid, in company with the biceps. It then passes over the 

 inner tuberosity, completely covered by the fibres of insertion of the subscapular}* 

 Upon a level with the superior edge of the latmiuius dorsi the muscle divides, the inner 

 portion passing down straight, but gradually widening to its insertion above the inner 



condyle, while the outer branch joins the biceps at about the level of the condyloid 

 foramen. Upon reflecting those fibres of the subscapulars which cover the coram. 

 brachialis as it passes over the inner tuberosity, there may be Been a delicate band of 

 muscular fibres, which arises in the acute angle made by the tendons of origin of the 

 biceps and the preceding muscle and appears to take rise from the common aponeurosis 

 of origin of these two muscles, and which is inserted into the outer portion of the inner 

 tuberosity of the humerus 2 . Its fibres are as nearly parallel to those of the subscapular' 

 as those of any broad muscle can be which converge towards their terminal ion. Is this 

 slip to be regarded as an outlying element of the subscapularis, or as the representation 

 of the short variety of the coraco-brachialis which has dropped short of its ordinary 



insertion 



<y 



In Macropus ruficollis this muscle appears to be represented by the « short van, 



of Wood only, but presented some note-worthy peculiarities, a description of which I 



subjoin in a footnote 3 . This variety only is, moreover, present in the M ombat, bon| 



Waterhouse 



already cited, figures (pi. ii. fig. 4) and describ 



(p. 7) an arra^ement in this specie, of the nbres of the **g++v~* _*. to h, £ ,1 ,,! u 



^ f/ c* & r -. . -.• , :—*:«■ „f tVin euLsmnulrirts. fck or! to insertion sc tail 



existing in the Tamandua. 



su capillar ," cot te insertion 

 glisse 



du biceps." 



3 



permission 



Student 



• Student's Note-Book : " ±rom ine c«^^ ~~ u and ig .^ 



with, the upper fibres of the .****•; * "»~ ^2^*^ Mediately below the insertion of 



divisible into two fascicles-oi wMcn rne ^ r ^ ^ ^ m ^ humerus ^.^ 



the subscapulars, and at right angles to it, while tne larger i 

 . . f ' , . , «._* -#«».- ^nninined teres major and fetaswniw flow. 



description of the wraeo-braMUs in afacr^wi ^an » :— " A thir, 



*rom the same source l borrow ure «»«w~* ■ f h mo . hyoid . 



muscular slip arises front the superior horde, o the scapula nc ft . ^ ^ ( 



It is separabL for an 



half 



umem 



downv 



inch and a half from the subscapula ris, over 



tendon of the biceps, where it glides over the inner ^-^ - -- ■- ^ inS( ition of the terc8 major . 



to be inserted on the inner side of the humerus, above, but m P 



overlying and giving fibres to the inner head of the triceps. 



